Global Patent Index - EP 0039836 A3

EP 0039836 A3 19820519 - A SCANNING HEAD FOR AN OPTICAL DISC SYSTEM

Title (en)

A SCANNING HEAD FOR AN OPTICAL DISC SYSTEM

Publication

EP 0039836 A3 19820519 (EN)

Application

EP 81103226 A 19810429

Priority

  • CA 351721 A 19800512
  • US 14976580 A 19800514

Abstract (en)

[origin: US4337531A] In a scanning head for an optical disc system, a light beam from a laser is transmitted through a monomode optical fiber and then focussed on a record carrying surface of an optical disc by a converging lens. The end of the fiber can be reoriented within orthogonal planes perpendicular to the plane of the record carrying surface by transducers so as to correct for tracking and timing errors. The laser diode can function both as an emitter and, in an external cavity mode, as a detector of light reflected from the disc. Drive to the transducers is dependent on tracking and speed error signals generated from the detected light. For tracking and speed error compensation, only lens fiber end, and, optionally, a collimating lens, which are of negligible weight, need be moved rather than the entire scanning head. This provides a simple structure having a high frequency response and low power consumption.

IPC 1-7

G11B 7/08; G11B 7/12

IPC 8 full level

G02B 26/10 (2006.01); G11B 7/09 (2006.01); G11B 7/12 (2006.01); G11B 7/123 (2012.01); G11B 7/13 (2012.01); G11B 7/135 (2006.01); G11B 7/1384 (2012.01)

CPC (source: EP US)

G11B 7/0937 (2013.01 - EP US); G11B 7/123 (2013.01 - EP US); G11B 7/13 (2013.01 - EP US); G11B 7/1384 (2013.01 - EP US); G11B 7/0901 (2013.01 - EP US); G11B 7/0909 (2013.01 - EP US)

Citation (search report)

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

US 4337531 A 19820629; CA 1132258 A 19820921; EP 0039836 A2 19811118; EP 0039836 A3 19820519; JP S573237 A 19820108

DOCDB simple family (application)

US 14976580 A 19800514; CA 351721 A 19800512; EP 81103226 A 19810429; JP 7026681 A 19810512